Secret Is Becoming The Next Tinder

At least, nothing indicates that it is. Its app store rankings fluctuate wildly and often don't register in the top 1,500 overall -- compared to its bigger, brasher rival Whisper, which is usually in the top 200. Secret won't discuss growth numbers, but a source told Forbes's Parmy Olson in April that Secret had less than 1 million downloads, and venture capitalists talk openly about its low Android download numbers.

But investors clearly have high hopes for the app, to the tune of $25 million in a Series B funding round announced Monday -- on top of an $8 million round in March.

The app lets users post secrets and share them with those connected to them -- friends, friends of friends, users nearby, and now Facebook friends, a feature announced Monday. It's designed to foster open conversation on touchy topics, and it often does that well.

But those open, honest conversations haven't taken off. What has? Sexy Secret.

Since it launched in January, Secret has grown from a tech-gossip app to a place where scrolling through a feed can take you from "I love my dog" to "I could really use a night of rough sex" -- and rough sex is on the tamer end of the spectrum.

When someone posts a funny Secret, it can get thousands of likes, but few comments. It's the open-ended, sexual secrets that end up attracting heated, back-and-forth responses. And the comments are usually more logistical than philosophical: "Are you a guy or girl" and "Where you at?"

In the past few months on Secret, raunchy posts pop up on my feed more and more often: A guy details (with florid prose) an encounter with a girl that leads to sex with her mother as well; another man describes, in Penthouse Letters style, a woman who flashes him secretly on a crowded Muni bus; and a set of men and women go back and forth in a comments section trying to meet up to celebrate a shared passion for cunnilingus.

Secret's different for every user, so not everyone will see the same content. But racy posts are no surprise -- humans are hard-wired to find sex interesting, and it's often not something discussed in public. That's where Secret might play a particularly vital role.

Secret co-founder and CEO David Byttow already sees Secret's thread discussions as more important than the secret itself. The secret is just a spark, he told Forbes -- the fire is the talk that comes after.

"It's not just that thing, that secret, the few words -- it's actually all the discussion around it," he said in a recent interview. "We have content that would fill hundreds of thousands of books should someone really want to read the dialogues. I think surfacing that is really valuable."

This user might not have been looking for company, but Secret's commenters are eager to meet up.

Of course, a lot of those dialogues would be "Are you in SF?" and "Hit me up on anonyfish" -- the anonymous messaging app that Secret users have started to turn to en masse to arrange sexual meetups after they begin a discussion on Secret.

All of this is aided by Secret's location-based algorithm and its easy-to-use conversation flow. Users are shown secrets from friends and from users nearby, ranging from several miles away to the coveted "<100 m" -- just like Tinder favors people potential dates who are nearby or have mutual friends.

Byttow said that the locations of secrets, which are saved at the moment the secret is posted, are sometimes fuzzed a bit to protect user privacy. But clearly, the "<100 m" distance was enough for a couple of lovebirds to bridge the gap between Secret and real life. In this case, it acted as a new Tinder where nearby interested parties met through their words, not their profile photos.

The conversation aspect of Whisper, Secret's biggest rival, is not nearly as fluid or inviting. Instead, it favors standalone secrets paired with one-off replies or secrets on similar topics. Only Secret makes users want to jump in on an ongoing conversation -- and that differentiation could be key to growth if it's struggling to gain momentum.

If Secret is willing to embrace raunchier content (or at least not tamp it down), it could see a growing audience. Tumblr mostly embraced its "porn problem," and as of a year ago, 16.5 percent of its traffic is sexual content, and 22 percent of external traffic referrals to Tumblr are from adult websites. Porn helps keep Tumblr strong.

Byttow did not answer questions about his plans for Secret's not-safe-for-work content. Its community guidelines ban nudity and graphic content.

But the startup is already making changes to the app that could favor this kind of content, whether that's the goal or not. On Monday, it announced a "collections" features on its website that pulls together Secret content on different topics -- "work," "funny," "dating," etc. It's a step toward a future on Secret where users' streams are more curated based on the topics they like -- as measured by the secrets they "like" and comment on. If users don't want to see sexy content, the algorithm could learn not to show it to them, and people who want to get a kick out of the app can still enjoy it.

Secret is also working on a private messaging feature in the app, the founders said in May. That's certainly an endorsement for users who meet on Secret to be able to take things to a private venue and meet up in real life.

Byttow said that one way to keep some control on the tone and feel of the app is by showing users content that is encouraged, especially for the first few secrets a new users sees. It's important that they strike the right tone and make a user feel welcome -- just like Tinder tends to line up a few people who have already swiped right on you whenever you log back into the app, so you get a nice reaffirmation every time you return.

"I fully believe that beauty begets beauty," Byttow said at a panel at Google's I/O developers conference last month. "If you join and see something extremely negative, hurtful, or not safe for work, you're like, 'What is this? What's going on?'"

"Like the names of the colors -- we didn't do pink or red, we did peony or cupid, lavender, cobalt," he told Forbes. "It's a little bit airy and fantastical, I guess. Just to make it always kind of reinforce that this is a well-lit space. I really like those little touches."

It's unclear if "peony" or "cupid" will stop users from posting crude content -- and maybe crude content will be tolerated. A $100 million valuation means investors will pressure the app to grow, and its moves to tailor its content into categories and introduce private messaging suggest it hasn't ruled out a sexy source of growth yet.

"Secret is essentially a form of online graffiti," wrote Index Ventures' Danny Rimer in a blog post explaining why the firm backed Secret. Hopefully he's okay with the graffiti occasionally being a "for a good time" bathroom stall scrawl.

Follow me on Twitter at @ellenhuet, find more of my stories on Forbes and send me tips or feedback at ehuet at forbes.com.

I'm a San Francisco-based reporter for Forbes' tech team. I cover technology news and write about how tech affects the people who create it, use it or live in a place full of it. Before Forbes, I covered tech culture for the San Francisco Chronicle and cut my teeth as a bre...